Champions Spain were knocked out of the Davis Cup as favourites Russian Tennis Federation booked their spot in the quarter-finals with a thrilling victory in Madrid.

Spanish duo Marcel Granollers and Feliciano Lopez needed to win their doubles decider to send Spain through at Serbia's expense, but Aslan Karatsev and Andrey Rublev came from a set down seal a 4-6 6-2 6-4 victory and top spot for Russia in Group A.